Hartge H1

Nick Hall opens the bonnet of this astonishingly quick hatch

5.0-litre Hartge H1

Sometimes words fall short. In this instance that open-mouthed came down the back straight of a small test track in France at an indicated 145mph, V8 roaring under the bonnet, in what looked for all the world like a BMW 1 Series. It was truly nuts.

This car might look like a 1 Series with a lairy bodykit, but those Merzig numberplates are a dead giveaway for the tuning connoisseur. This is a Hartge and lurking under that unassuming bonnet is a monster of an engine: a 5.0 litre V8 from the E39 M5 to be precise.

Now if you’ve already dismissed this as a tuned piece of garbage, you’re wrong. Hartge does tune cars, but this one is such a comprehensive piece of work that it comes with full registration documents and a new name, the H1. Hartge, like Ruf, 9ff and a few other elite spannermen, get full approval as manufacturers, that’s a badge of honour they’re rightly proud of.

And their signature dish is a large engine jammed into a small BMW. They’ve been at it for more years than Herbert Hartge cares to remember, but this was one of the hardest conversions to date.

Forget wedging the M5 engine under the bonnet, it’s surprisingly roomy under there and, though the powerplant looks like its pressed against the steering wheel when the bonnet’s up, the V8 fitted comfortably. No, the real problem was one that’s becoming all too familiar for tuners everywhere: marrying the electronics.

Rocket-powered bread van

It was worth the effort, though, as this bread van is now near rocket-powered. Not only will it blast to 60mph in a borderline stupid 4.8s, that brute force under the bonnet will propel this aerodynamic brick wall all the way to 188mph. In gear acceleration is intense, too, thanks to 480lb/ft of torque heading through those rear wheels. The rear axle started life in the M3, and still needed reinforcement.

And the noise, courtesy of those centrally mounted twin-exit pipes, is immense, like a rolling thunder that left bystanders with that same vacant, open-mouthed confusion as we rolled through town.

Like the roundel from whence it came, though, this machine only slips when you ask it to. Kept under 4,000rpm on the public roads the Hartge is docile as a big dumb dog, thanks to the duality of BMW’s double VANOS timing system. You can soak up the carbon-fibre splashed interior, bucket seats, gloriously precise short shift, you can even listen to music and relax, a bit.

But push the throttle that little bit further towards the redline and it’s like flushing the car’s system with rabies, leaving the driver frothing at the mouth.

It can slide all the way through the first four gears, even in a straight line, and it shimmied on me down the main straight at this short track at speeds of up to 140mph as the 19-inch front wheels hit puddles. A quick correction, which possibly wasn’t even necessary, the car regained its composure and took off again for the next apex.

Miles of smiles

But it’s in the corners this machine leaves the realms of the reason. Radicals may leave it half a lap behind and an Exige would probably destroy this comical little car on track, but if smiles count for more than bragging rights, then this is the outright winner. You can take this thing into bends backwards.

See Hartge knows not all of its customers have as much skill as they’d like, or even believe they possess, and so their craziest cars come with a margin of error normally afforded only to Labour ministers. It’s a limited slip differential, with a 0-99 per cent locking mechanism.

Which was lucky, because as we headed across the French border the heavens opened and dumped a swimming pool on the tarmac. A magazine that is now a customer, and so will remain nameless, turned up with an M6 and didn’t venture outside until early afternoon, but in the H1 it was game on in standing water.

Out of the hairpins the H1 is perfectly happy at 45 degrees, with half a turn of opposite lock and the rear wheels spinning up a treat. On a dry track we’d have cooked the tyres in a few laps and even in the wet the sheer balance and adjustability of this 450bhp go-kart defied belief. It’s a driver’s dream, and reminiscent of one of the all-time great BMWs.

The H1 is just 20cm longer than the almighty Z3M Coupe, 1cm wider, weighs 20kg less and boasts more than 130 extra horses. And anyone thinking weight distribution will be in for a pleasant surprise.

Think about the layout of an inline six in the original 1 Series and the heavier but shorter V8. Despite adding close to 200kg to the overall package, the bigger M5 unit doesn’t screw the weight distribution so you’re left with 52:48 front to rear. Yes it’s ever so slightly nose heavy, but it’s hardly difficult to cure that with a hefty dose of power and, with the LSD, you don’t need to be The Stig to catch it..

Not a bad recipe really, and one that has previously worked with devastating effect on their Z4 conversion.

Not quite faultless

Having driven that mental machine, it was no surprise the Hartge can hang it out with the best of them and you can’t help thinking that, freed from all constraints, these are the cars those M Division men would be making themselves.

There’s no pitch and wallow in the suspension, this car sat 30mm lower than the 1 Series thanks to Hartge’s in-house system. It’s firm, but Hartge’s kit is amazingly forgiving on the open road. In fact it’s almost the perfect car, almost.

The engine could go forever and this car could take the abuse, but it has just one nervous habit that takes it beyond the remit of an everyday driver. You need to match the revs on the downchange when pressing on with the largely forgotten art of heel-and-toe.

Fail to do this and the back axle locks, sending the H1 into a slide. You can stay off the engine braking and rely on the massive eight-pot front callipers working with 380mm cross-drilled floating rotors, but pushing the H1 V8 to its limits requires racing skills.

Mid-way through the project I contacted Hartge who were convinced, due to spiralling costs, they would not sell a single one of these cars. Before they’d even finished this one, though, there were three sales in the offing.

It’s a fantastic car, but then the real world intrudes. Hartge’s H1 might just be the most fun with clothes on, but you’ll have to drive in a brand new 1 Series AND hand over €70,000.

That much cash can put a smile on your face, take your breath away and leave you gaping and vacant in any number of ways. It doesn’t add up as a rational purchase, but it’s more fun than should reasonably be allowed.

And next time you’re pulling out to decimate a 1 Series BMW with a lairy bodykit, just remember to check the plates. What lies beneath could be about to tear you apart.